Medical probes have the ability to provide images from inside the patient's body. Considering the potential damage to a human body caused by the insertion of a foreign object, it is preferable for the probe to be as small as possible. Additionally, the ability to image within small pathways such as small vessels, small ducts, small needles, cracks etc., requires a small probe size.
One useful medical probe employs a spectrally encoded endoscopy (“SEE”), which is a miniature endoscopy technology that can conduct high-definition imaging through a sub-mm diameter probe. With SEE, broadband light is diffracted by a grating at the tip of the fiber, producing a dispersed spectrum on the sample. Light returned from the sample is detected using a spectrometer; and each resolvable wavelength corresponds to reflectance from a different point on the sample. The principle of the SEE technique and an SEE probe with a diameter of 0.5 mm, i.e., 500 μm have been described in D. Yelin et al., Nature Vol. 443, 765-765 (2006). SEE can produce high-quality images in two- and three-dimensions.
One of the technical challenges for fabricating SEE probes has been to conduct forward-view SEE imaging (also called front-view SEE imaging). Previously, SEE probe designs that utilize double-prism grating prism (DP GRISM) have been proposed for forward-view imaging by publication U.S. 2011/0237892. While a previous publication (Optics Express, 11(2):120-4, 2003) demonstrated a spectrally-encoded confocal microscopy (SECM) probe that uses a DP-GRISM. However, the diameter of the probe was 10 mm, and there are numerous challenges in miniaturizing the DP GRISM to a size that is useable in SEE probe.
Accordingly, it can be beneficial to address and/or overcome at least some of the deficiencies indicated herein above, and thus to provide a new SEE probe that can view forward direction and an apparatus to use such a probe, e.g., for imaging in a small optics.